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The purpose of this paper is to present a scan matching simultaneous localization and mapping (SLAM) algorithm based on particle filter to generate the grid map online. It mainly focuses on reducing the memory consumption and alleviating the loop closure problem.

The proposed method alleviates the loop closure problem by improving the accuracy of the robot’s pose. First, two improvements were applied to enhance the accuracy of the hill climbing scan matching. Second, a particle filter was used to maintain the diversity of the robot’s pose and then to supply potential seeds to the hill climbing scan matching to ensure that the best match point was the global optimum. The proposed method reduces the memory consumption by maintaining only a single grid map.

Simulation and experimental results have proved that this method can build a consistent map of a complex environment. Meanwhile, it reduced the memory consumption and alleviates the loop closure problem.

In this paper, a new SLAM algorithm has been proposed. It can reduce the memory consumption and alleviate the loop closure problem without lowering the accuracy of the generated grid map.

Extensive efforts have been conducted on the real-time strategy (RTS) games. The purpose of this paper is the specific artificial intelligence (AI) challenges posed by RTS games; non-player character (NPC) is started out by collecting game-map resources to build up defenses and attack forces, to upgrade combat deployment.

The authors used weak AI fuzzy theory as the foundation for tunable development. With the fuzzy theory, the AI was more humanistic in its judgment process.

Well-developed AIs have been used brilliantly in various aspects in RTS games, especially in those developed by large production teams. For small production teams, how to develop an AI system in less time and at a lower cost is extremely important.

This study aimed to develop a system using player unit threat levels for NPC deployment and arrangement so that the further strategy would be adopted for NPCs in response to player actions.

The RTS games would become more challenging for players to play.

This paper aims to propose a novel robot kinematic calibration method based on the common perpendicular line (CPL) model to improve the absolute accuracy of industrial robots.

The deviation between the nominal and actual twists is considered the CPL transformation, which includes the rotation about the CPL and the translation along the CPL. By using the invariance of the reciprocal product of the two spatial lines, the previous deviation was analyzed in the neighbor space of the base frame origin. In this space, the line vector of the CPL contained only four independent parameters: two orientation elements and two moment elements. Thus, the CPL model has four independent parameters for the revolute joint and two parameters for the prismatic joint.

By simulations and experiment conducted on a SCARA robot and a 6-DOF PUMA robot, the effectiveness of the novel method for calibration of industrial robot is validated.

The CPL model avoided the normalization and orthogonalization in the iterative identification procedure. Therefore, identifying the CPL model was not only simpler but also more accurate than that of the traditional model. In addition, the results of the CPL transformation strictly conformed to the constraints of the twist.

Because submaps including a subset of the global map contain more environmental information, submap-based graph simultaneous localization and mapping (SLAM) has been studied by many researchers. In most of those studies, helpful environmental information was not taken into consideration when designed the termination criterion of the submap construction process. After optimizing the graph, cumulative error within the submaps was also ignored. To address those problems, this paper aims to propose a two-level optimized graph-based SLAM algorithm.

Submaps are updated by extended Kalman filter SLAM while no geometric-shaped landmark models are needed; raw laser scans are treated as landmarks. A more reasonable criterion called the uncertainty index is proposed to combine with the size of the submap to terminate the submap construction process. After a submap is completed and a loop closure is found, a two-level optimization process is performed to minimize the loop closure error and the accumulated error within the submaps.

Simulation and experimental results indicate that the estimated error of the proposed algorithm is small, and the maps generated are consistent whether in global or local.

The proposed method is robust to sparse pedestrians and can be adapted to most indoor environments.

In this paper, a two-level optimized graph-based SLAM algorithm is proposed.

The key challenge that urban cities in most developing and transitional economies is confronting is municipal solid waste (MSW) management. Waste separation is a critical component to successful recycling management in terms of enhancing the quality of recyclables, reducing MSW and optimizing incineration. The urge to actualizing sustained waste separation behavior has been hindered by potential barriers. This study aims to examine the influences of external and internal stimuli of targeted households' waste separation intention in parts of China.

A multifactor framework predicting the process that leads to waste separation attitude and behavioral intention is proposed. SEM analysis is conducted in SmartPLS based on 371 survey questionnaires collected in Nanning city in China.

Policy regulation is the biggest determinant of attitude among external stimuli, while awareness of consequence has the strongest relationship with an attitude among internal stimuli. Facilitating conditions, subjective norms and moral norms are all significant predictors of attitude. As a result, increasing positive attitude leads to enhance waste separation lifestyle.

This study adopts a cross-sectional design to investigate the waste separation intention of local households. Data collection is restricted to one point in time for every individual. A mixed method is recommended. Quantitative research can examine variables provided in existing literature with numerical analysis. Qualitative research might be helpful to identify other unknown factors. Also, the survey questionnaires employ a self-reported manner, and respondents might be overrating to avoid embarrassment.

Future research is recommended to engage observation at houses or at the waste-collecting points for actual waste separation behavior. Moreover, this study measures intention toward household waste separation, but whether this intention will eventually lead to waste separation behavior is not a guarantee. Future study is recommended to examine whether intention translates into actual waste separation behavior.

Emphasizing the importance of policy element as a direct influence toward attitude, this paper focuses on the waste separation attitude accumulated from external and internal stimuli, and, concurrently, waste separation behavioral intention is influenced by accumulated attitudes. The study provides relevant policy development information of three Asian countries to enhance their present and future policy directions for a sustainable household waste separation management process

This paper aims to study turbulent dispersion of a passive plume emitting from a single elevated line source of different elevations in a plane channel flow by using direct numerical simulation (DNS).

The investigation was conducted in both physical and spectral spaces, which includes an analysis of statistical moments and pre-multiplied spectra of the velocity and concentration fields. The pre-multiplied power spectra of the velocity and concentration fields are compared to identify the transition of the plume development from the turbulent convective stage to the turbulent diffusive stage.

It is observed that due to the presence of wall shear, the mean plume drifts toward the wall for the near-wall source release case. It is also observed that streamwise development of the plume is sensitive to both the source elevation and the downstream distance from the source. For the line source placed near the center of the channel, the plume development is dominated by the bulk meandering effects. However, for the plume emitting from the near-wall line source, it hits the ground soon after its release and becomes dominated by the wall shear. As the downstream distance from the line source increases, the streamwise development of the plume released from the near-wall line source transitions from a turbulent convective stage to a turbulent diffusive stage.

This paper represents an original DNS study of turbulent mixing and dispersion of a passive plume emitting from a line source of different elevations in a wall-bounded flow. This paper proposes a practical method to identify the transition of the plume development from the turbulent convective to the turbulent diffusive stages.

The purpose of this paper is to explore multilingual access in digital libraries and to present a case study of creating bilingual metadata records for the Tse-Tsung Chow Collection of Chinese Scrolls and Fan Paintings. The project, undertaken at the University of Wisconsin-Milwaukee Libraries, provides access to digital copies of calligraphic and painted Chinese scrolls and fans from the collection donated by Prof Tse-Tsung Chow (Cezong Zhou).

This paper examines the current approaches to multilingual indexing and retrieval in digital collections and presents a model of creating bilingual parallel records that combines translation with controlled vocabulary mapping.

Creating multilingual metadata records for cultural heritage materials is in an early phase of development. Bilingual metadata created through human translation and controlled vocabulary mapping represents one of the approaches to multilingual access in digital libraries. Multilingual indexing of collections of international origin addresses the linguistic needs of the target audience, connects the digitized objects to their respective cultures and contributes to richer descriptive records. The approach that relies on human translation and research can be undertaken in small-scale digitization projects of rare cultural heritage materials. Language and subject expertise are required to create bilingual metadata records.

This paper presents the results of a case study. The approach to multilingual access that involves research, and it relies on human translation that can only be undertaken in small-scale projects.

This case study of creating parallel records with a combination of translation and vocabulary mapping can be useful for designing similar bilingual digital collections.

This paper also discusses the obligations of holding institutions in undertaking digital conversion of the cultural heritage materials that originated in other countries, especially in regard to providing metadata records that reflect the language of the originating community.

The research and practice in multilingual indexing of cultural heritage materials are very limited. There are no standardized models of how to approach building multilingual digital collections. This case study presents a model of providing bilingual access and enhancing the intellectual control of cultural heritage collections.

The effectiveness of corporate governance is a major factor in forecasting firm performance. We examine the relationships among cross-listing, corporate governance and firm performance for a sample of Chinese cross-listed companies. We show that cross-listed firms display higher overall quality of corporate governance compared to non-cross-listed firms. Consequently better corporate governance results in higher operating performance. Our results support the bonding hypothesis of cross-listing. Furthermore, we also illustrate that the cross-listing status encapsulates the higher quality of corporate governance that leads to higher operating performance. When forecasting performance of cross-listing companies, it is therefore important to recognize the substitute effect between cross-listing and corporate governance.

The purpose of this paper is to present an approach which can evaluate the ability that successfully achieves command and control, both in qualitative and quantitative modes, to improve decision accuracy and speed, as well as construct an executable architecture for analyzing and verifying different decision projects.

By defining command and control (C2) decision architecture and decomposing C2 decision processes into measurable subfunctions, measures and metrics will be associated with each of the lowest level decomposed functions, and will be used to provide support for performance evaluation. Both Markov decision process analysis and conditional probability (CP) logic are used for modeling the decision‐making process of course of action (COA). Meanwhile, an executable architecture constructed by Petri net is applied to logic structural verification and performance evaluation.

The paper presents an idea and methodology for net‐centric command and control decision‐making process analysis.

The paper describes and decomposes C2 decision processes for complex missions in uncertain environments.

The paper could be an important reference of analysis and application in net‐centric command and control of decision making.

The paper combines methodology with qualitative methods (decision process decomposition), quantitative method (Markov decision process analysis and CP logic), as well as structural verification and performance evaluation.